A Method for Balancing Hybrid Torque-Vectoring Differential (H-TD) System with Optimized Counterweight
Hybrid torque-vectoring differential (referred as H-TD hereafter) is a differential system which integrates both torque-vectoring and electric hybrid functionality. The system is basically based on a conventional open differential and utilizes an electric motor to differentiate torque between two output shafts or to provide additional driving torque. However, the mechanism of the system inevitably gives rise to different equivalent rotational inertia of two output shafts, which might cause asymmetric traction force condition on two output wheels. So, this paper aims to give a solution to minimize the above-mentioned situation. Firstly, the constitution of H-TD mechanism, and operation modes of the system are introduced. After that, the cause of the unbalanced situation is discussed and a solution combining a counterweight and optimization design is proposed. Regarding the optimization design, the dynamic model is established to formulate the optimization problem, and the design constraints are defined. Lastly, Genetic Algorithm method is used to solve the optimization problem and the effect of the proposed solution is verified by using numerical simulation.
KeywordsTorque-Vectoring Differential Equivalent Rotational Inertia Counterweight Optimization Genetic Algorithm
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- 1.Encyclopaedia Britannica Inc., “Encyclopaedia Britannica,” 15th ed: New York: Black Dog & Leventhal Publishers, 2008.Google Scholar
- 2.Kinsey, J., “The Advantages of an Electronically Controlled Limited Slip Differential,” SAE Technical Paper 2004-01-0861, 2004, doi: https://doi.org/10.4271/2004-01-0861.
- 3.Garrett, T. K., Newton, K., and Steeds, W., “Motor Vehicle, 13th Edition” ISBN: 978-0768006391.Google Scholar
- 4.K. Mimura, “Differential Gear.” US Patent 6120407, issued Sep. 19, 2000.Google Scholar
- 5.K. Sawase, Y. Ushiroda and T. Miura, “Left-Right Torque Vectoring Technology as the Core of Super All Wheel Control (S-AWC),” Mitsubishi Motors Technical Review, no. 18, pp. 16-23, 2006.Google Scholar
- 6.Lin, C.K., Cheng, P.J., Chung, Y.J. and Liu, T., “Conceptual Design and Analysis of Hybrid Torque-Vectoring Differential (H-TD)”, SAE Technical Paper (Pending)Google Scholar
- 7.Sung, J.C., Liu, T., “The Effect of a Motor-controlled Torque Vectoring Differential on the Vehicle Handling Dynamics,” presented at CSMMT 2017, Taiwan, Nov. 17-18, 2017Google Scholar
- 8.American Gear Manufacturers Association, ANSI/AGMA 2001-D04, Fundamental Rating Factors and Calculation Methods for Involute Spur and Helical Gear Teeth. Alexandria, VA: American Gear Manufacturers Association, 2004.Google Scholar
- 9.W. Huang, L. Fu, X. Liu, Z. Wen, and L. Zhao, “The Structural Optimization of Gearbox Based on Sequential Quadratic Programming Method,” in Second International Conference on Intelligent Computation Technology and Automation, China, 2009.Google Scholar